Efficient way to Sort vector based time

I have vector which has 50000+ strings Element. I need to sort it based on the time given in each string of vector element

EX :Need to sort based on time from each string 26.79 , 26.70 , 26.74

10571 2019/12/30 15:40:13.692465 26.79  106  share 524409 log info edit 1 twitter::getallprofile() invoked
10571 2019/12/30 15:40:13.692465 26.70 106  share 524409 log info edit 1 twitter::getallprofile() invoked
10571 2019/12/30 15:40:13.692465 26.74
106  share 524409 log info edit 1 twitter::getallprofile() invoked

Result to be sorted based on the 4th string time stamp as below

10571 2019/12/30 15:40:13.692465 26.70  106  share 524409 log info edit 1 twitter::getallprofile() invoked
10571 2019/12/30 15:40:13.692465 26.74 106  share 524409 log info edit 1 twitter::getallprofile() invoked
10571 2019/12/30 15:40:13.692465 26.79 106  share 524409 log info edit 1 twitter::getallprofile() invoked